A terrestrial digital television signal receiver

Abstract

The utility model relates to signal processing technical field, and disclose a kind of ground digital television signal receiver, including shell assembly and signal processing component, the signal processing component includes PCB board, external antenna interface, charging interface and OTG-Type-C interface;The surface of one end of the PCB board is respectively encapsulated with external antenna interface and charging interface;The surface of the other end of the PCB board is encapsulated with OTG-Type-C interface;The signal processing component is installed in the inside of the shell assembly, and the one end opening portion of the shell assembly is connected with cover plate.The utility model passes through the whole process cooperation of "radio frequency receiving pretreatment→DVB-T2, DVB-T, ISDB-T, SBTVD-T, ATSC1.0, ATSC3.0 demodulation decoding→USB interface adaptation→terminal APP processing", realizes following core value: solve the original defect that mobile terminal cannot receive ground digital television signal;Adopt the cooperative architecture of "hardware demodulation+USB protocol adaptation+APP software processing", without hardware modification to mobile terminal, reduce application threshold.

Description

Technical Field

[0001] This utility model relates to the field of signal processing technology, specifically to a terrestrial digital television signal receiver. Background Technology

[0002] With the continuous evolution of digital television technology, terrestrial digital television has become an important part of global digital television services due to its core advantages such as wide-area coverage, no reliance on cellular networks / broadband, and low operating costs. Among these, DVB-T2, DVB-T, ISDB-T, SBTVD-T, ATSC1.0, and ATSC3.0 (terrestrial digital television standards) have been developed by different countries based on their national conditions and application scenarios. These standards have enabled efficient signal transmission within the 470-860MHz VHF / UHF bands through technologies such as Orthogonal Frequency Division Multiplexing (OFDM) and Low-Density Parity-Check (LDPC), supporting stable transmission of high-definition (HD) and even ultra-high-definition (UHD) audio and video content, and are widely used for television signal coverage in urban, suburban, and remote areas.

[0003] Meanwhile, with the widespread adoption of mobile smart terminals (such as Android phones and tablets) and the emergence of dongles for receiving digital television signals, a user experience has been enhanced, enabling viewers to watch TV programs anytime, anywhere and access the latest information. This addresses the shortcomings of traditional fixed television, which is limited by its location, consumes data for streaming video, relies on network coverage, and suffers from significant limitations in scenarios with no or weak network coverage, such as outdoors, while traveling, or for emergency communication. However, mobile terminals, limited by size and power consumption design, generally fail to integrate terrestrial radio frequency signal reception and demodulation hardware for DVB-T2, DVB-T, ISDB-T, SBTVD-T, ATSC1.0, and ATSC3.0 standards to acquire terrestrial digital television signals. Therefore, a terrestrial digital television signal receiver is proposed. Utility Model Content

[0004] The purpose of this invention is to provide a terrestrial digital television signal receiver to bridge the technological gap between mobile terminals and terrestrial digital television signals in the aforementioned background technology. It will become a key hardware for mobile viewing of terrestrial television in network-free scenarios and will play an irreplaceable role in scenarios such as emergency broadcasting, outdoor entertainment, and information access in remote areas.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a terrestrial digital television signal receiver, comprising a housing assembly and a signal processing assembly, wherein the signal processing assembly includes a PCB board, an external antenna interface, a charging interface and an OTG-Type-C interface; An external antenna interface and a charging interface are respectively encapsulated on one end surface of the PCB board; The other end of the PCB board is encapsulated with an OTG-Type-C interface; The signal processing component is installed inside the housing assembly, and a cover plate is connected to one end opening of the housing assembly.

[0006] Preferably, the housing assembly includes an outer shell and a first through hole, the other end of the outer shell having a first through hole, the first through hole being adapted to the OTG-Type-C interface, and the OTG-Type-C interface passing through the first through hole.

[0007] Preferably, the cover plate has a second through hole and a third through hole, which correspond to the external antenna interface and the charging interface, respectively.

[0008] Preferably, the charging interface is a TPYC charging interface, and the external antenna interface is an MCX external antenna interface.

[0009] Preferably, one end of the outer casing is provided with an opening, which is adapted to the cover plate and is provided with a buckle.

[0010] Compared with the prior art, the present invention, by adopting the above technical solution, has the following technical effects: This utility model achieves the following core value through the collaborative process of "RF reception preprocessing → DVB-T2, DVB-T, ISDB-T, SBTVD-T, ATSC1.0, ATSC3.0 demodulation and decoding → USB interface adaptation → terminal APP processing": To address the inherent limitation of mobile terminals (phones, tablets) being unable to receive terrestrial digital television signals; It adopts a collaborative architecture of "hardware demodulation (Sony CXD6820GL, CXD6822GL, CXD6821GL chips) + USB protocol adaptation + APP software processing", which does not require hardware modification of mobile terminals (does not increase the hardware complexity of mobile terminals) and lowers the application threshold. This enables mobile devices to watch live broadcasts using only terrestrial digital television signals in scenarios without cellular network traffic or WiFi (such as outdoors, while traveling, or in areas without network coverage), thus expanding the application scenarios and user base of terrestrial digital television. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is an exploded view of the structure of this utility model; Figure 2 This is a schematic diagram of the overall structure of the present invention. Figure 1 ; Figure 3 This is a schematic diagram of the overall structure of the present invention. Figure 2 ; Figure 4 This is a schematic diagram of the overall structure of the present invention. Figure 3 .

[0013] Explanation of reference numerals in the attached drawings: 10, housing assembly; 101, outer casing; 102, first through hole; 20. Cover plate; 201. Second through hole; 202. Third through hole; 30. Signal processing components; 301. PCB board; 302. External antenna interface; 303. Charging interface; 304. OTG-Type-C interface. Detailed Implementation

[0014] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0015] It should be noted that the structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which this application can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size should still fall within the scope of the technical content disclosed in this application, provided that they do not affect the effects and purposes that this application can produce.

[0016] Example In existing technologies, traditional fixed television is limited by the scenarios in which it is broadcast, while streaming video consumes data and relies on network coverage, resulting in significant shortcomings in scenarios with no or weak network coverage, such as outdoors, travel, and emergency communications. However, mobile terminals, limited by size and power consumption design, generally do not integrate terrestrial radio frequency signal reception and DVB-T2 demodulation hardware, and therefore cannot directly acquire terrestrial digital television signals.

[0017] Please see Figures 1-4 This utility model provides a technical solution: a terrestrial digital television signal receiver, including a housing assembly 10 and a signal processing assembly 30, wherein the signal processing assembly 30 includes a PCB board 301, an external antenna interface 302, a charging interface 303 and an OTG-Type-C interface 304; An external antenna interface 302 and a charging interface 303 are respectively encapsulated on one end surface of the PCB board 301; The other end of the PCB board 301 is encapsulated with an OTG-Type-C interface 304; The signal processing component 30 is installed inside the housing component 10, and a cover plate 20 is connected to one end opening of the housing component 10.

[0018] In this specific embodiment, the housing assembly 10 includes a housing 101 and a first through hole 102. The other end of the housing 101 is provided with the first through hole 102. The first through hole 102 is adapted to the OTG-Type-C interface 304, and the OTG-Type-C interface 304 passes through the first through hole 102.

[0019] In this embodiment, the cover plate 20 has a second through hole 201 and a third through hole 202 through it, respectively. The second through hole 201 and the third through hole 202 correspond to the external antenna interface 302 and the charging interface 303, respectively.

[0020] Specifically, in this embodiment, the charging interface 303 is a charging TPYC interface, and the external antenna interface 302 is an MCX external antenna interface.

[0021] Specifically in this embodiment, one end of the outer shell 101 is provided with an opening, which is adapted to the cover plate 20 and is provided with a buckle.

[0022] Step 1: The terrestrial digital television signal (specifically, the VHF / UHF band signal transmitted by the TV station, with a frequency range of 470-860MHz) is captured by the telescopic antenna and then transmitted through the MCX external antenna interface 302 to the tuner module of the dedicated processing chip (model Sony CXD6820GL, CXD6822GL, CXD6821GL).

[0023] The tuner module performs the following processes in sequence: Low-noise amplifier (LNA): Suppresses ambient noise, reduces interference during signal transmission, and improves the signal-to-noise ratio by using low-noise amplifier circuits; Automatic gain control (AGC): Dynamically adjusts the gain parameter based on the input signal strength to ensure that the signal strength remains stable within the preset processing range; Down-conversion: converting high-frequency radio frequency signals into baseband signals that can be processed by subsequent demodulation stages.

[0024] The technical effect of this step is to supplement the terrestrial digital television signal reception capability of mobile terminals (such as mobile phones and tablets), which is equivalent to integrating a "terrestrial digital television signal receiving unit + signal preprocessing unit" externally into the mobile terminal, thus solving the problem that mobile terminals do not have native terrestrial digital signal reception function.

[0025] Step Two: The baseband signal output from step one is an unparsed serial digital stream. It needs to be demodulated and decoded according to DVB-T2, DVB-T, ISDB-T, SBTVD-T, ATSC1.0, and ATSC3.0 (Digital Video Broadcasting - Terrestrial Standard) to extract valid audio, video, and signaling data. The specific process is as follows: OFDM demodulation The baseband signal is demodulated using Orthogonal Frequency Division Multiplexing (OFDM) to extract the Physical Layer Pipe (PLP) data from the signal. At the same time, the preamble symbols (P1 / P2) in the signal are parsed to obtain the core transmission parameters of the terrestrial digital television signal (including but not limited to the number of FFT points, guard interval, modulation method, etc.), thereby realizing the identification and confirmation of the signal transmission format rules.

[0026] Error correction processing The decoding mechanism employs a concatenation of LDPC (Low Density Parity-Check) code and BCH code to correct bit errors caused by channel fading and electromagnetic interference during signal transmission. This decoding mechanism supports a bit rate range of 1 / 2 to 5 / 6, which can adapt to different signal quality scenarios and effectively avoid audio and video stuttering, screen tearing and other problems caused by insufficient signal strength or interference.

[0027] Frame reassembly and data separation Perform a reassembly operation on the demodulated signal frame to separate the common PLP from the service PLP: Public PLP: Contains service signaling data (such as channel identifier, frequency band information, etc.); Business PLP: Contains raw audio and video data; The final output is a 188-byte TS stream conforming to the MPEG-2 TS (transport stream) standard, which effectively separates the "channel signaling data" from the "playable audio and video data".

[0028] Step 3: The TS stream output in step two is serial data, which cannot be directly recognized by mobile terminals with USB interfaces. It needs to be converted and adapted to the protocol through a USB bridge chip. The specific operation is as follows: Clock and data buffer adaptation: The clock rate of the TS stream is calibrated to synchronize with the USB transmission clock; at the same time, the TS stream data is temporarily stored through the data buffer unit to avoid stuttering or packet loss caused by mismatch in data transmission rate.

[0029] USB protocol encapsulation: The adapted TS stream is encapsulated into USB Bulk Transfer protocol data packets; this transmission protocol features high stability for large data transmission and a robust error retransmission mechanism, making it suitable for the continuous transmission needs of audio and video streams.

[0030] Device type identification and adaptation: The receiver is described as a "video input device" (instead of a general storage device, such as a USB flash drive) in accordance with the USBVideoClass specification.

[0031] The technical effect of this step is to establish a communication link between the receiver and the mobile terminal, realize the stable transmission of TS stream between the two through the USB interface, and solve the compatibility problem between serial TS stream and mobile terminal USB interface.

[0032] Step Four: Once the Android mobile terminal recognizes the aforementioned receiver via USBOTG (USBOn-The-Go) function, the accompanying application (APP) performs the following playback preprocessing and output operations: Channel scanning and channel list generation The APP controls the receiver to traverse all frequency points within the target frequency band, parse the Network Information Table (NIT) and Service Description Table (SDT) in the signals of each frequency point, extract information such as channel identifiers and channel names, and generate a list of channels that users can intuitively identify (such as "XX Satellite TV" or "XX Local TV").

[0033] TS stream real-time demultiplexing Real-time demultiplexing is performed on the TS stream transmitted via the USB interface to separate the audio and video basic stream data packets (PES packets), thereby separating the audio and video data from other auxiliary data (such as signaling data) and providing clean audio and video data for subsequent decoding.

[0034] Hardware-accelerated decoding The app calls the Android terminal's MediaCodec application programming interface (API) to start the terminal's hardware decoding module and decode the audio and video data in the PES packet: Video decoding: Supports H.264 and HEVC (H.265) encoding formats; Audio decoding: Supports AAC and AC3 encoding formats; Hardware acceleration reduces the CPU load on the terminal, avoiding decoding delays or stuttering.

[0035] Audio and video playback and interaction The decoded audio and video signals are rendered onto the display interface of the Android terminal, while providing electronic program guide (EPG) interactive functions (including but not limited to program schedule query, program reservation, program playback control, etc.); ultimately realizing the application scenario that "after the user launches the APP, they can directly complete channel selection, live viewing and program interaction".

[0036] Summarize, This utility model achieves the following core value through a collaborative end-to-end process: "RF reception preprocessing → DVB-T2, DVB-T, ISDB-T, SBTVD-T, ATSC1.0, ATSC3.0 demodulation and decoding → USB interface adaptation → terminal APP processing": To address the inherent limitation of mobile terminals (phones, tablets) being unable to receive terrestrial digital television signals; It adopts a collaborative architecture of "hardware demodulation (Sony CXD6820GL, CXD6822GL, CXD6821GL chips) + USB protocol adaptation + APP software processing", which does not require hardware modification of mobile terminals (does not increase the hardware complexity of mobile terminals) and lowers the application threshold. This enables mobile devices to watch live broadcasts using only terrestrial digital television signals in scenarios without cellular network traffic or WiFi (such as outdoors, while traveling, or in areas without network coverage), thus expanding the application scenarios and user base of terrestrial digital television.

[0037] The specific chip standards are as follows: 1. The dedicated processing chip Sony CXD6820GL supports: DVB-T2, DVB-T, ISDB-T, SBTVD-T; 2. The dedicated processing chip Sony CXD6822GL supports: DVB-T2, DVB-T, ISDB-T, SBTVD-T, and ATSC1.0; 3. The dedicated processing chip Sony CXD6821GL supports: DVB-T2, DVB-T, ISDB-T, SBTVD-T, ATSC1.0, and ATSC3.0.

[0038] Those skilled in the art will understand that the features described in the various embodiments and / or claims of this utility model can be combined or combined in various ways, even if such combinations or combinations are not explicitly described in this utility model. In particular, the features described in the various embodiments and / or claims of this utility model can be combined or combined in various ways without departing from the spirit and teachings of this utility model. All such combinations and / or combinations fall within the scope of this utility model.

Claims

1. A terrestrial digital television signal receiver, comprising a housing assembly (10) and a signal processing assembly (30), characterized in that: The signal processing component (30) includes a PCB board (301), an external antenna interface (302), a charging interface (303), and an OTG-Type-C interface (304). An external antenna interface (302) and a charging interface (303) are respectively encapsulated on one end surface of the PCB board (301). The other end of the PCB board (301) is encapsulated with an OTG-Type-C interface (304). The signal processing component (30) is installed inside the housing assembly (10), and a cover plate (20) is connected to one end opening of the housing assembly (10).

2. A terrestrial digital television signal receiver according to claim 1, characterized in that: The housing assembly (10) includes a housing (101) and a first through hole (102). The other end of the housing (101) is provided with the first through hole (102). The first through hole (102) is adapted to the OTG-Type-C interface (304). The OTG-Type-C interface (304) passes through the first through hole (102).

3. A terrestrial digital television signal receiver according to claim 1, characterized in that: The cover plate (20) has a second through hole (201) and a third through hole (202) through it, respectively. The second through hole (201) and the third through hole (202) correspond to the external antenna interface (302) and the charging interface (303), respectively.

4. A terrestrial digital television signal receiver according to claim 1, characterized in that: The charging interface (303) is a charging TPYC interface, and the external antenna interface (302) is an MCX external antenna interface.

5. A terrestrial digital television signal receiver according to claim 2, characterized in that: One end of the outer shell (101) is provided with an opening, which is adapted to the cover plate (20) and is provided with a buckle.

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